But some observant and loyal fans have noticed that while little Louis will be christened in the same London royal chapel as his older brother Prince George, Charlotte was baptised at the Church of St Mary Magdalene in Sandringham.

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However, it turns out that the reason for this is simple – it's purely down to 'personal preference', and the couple's location at the time of the Cambridge children's christenings.

Kensington Palace told Prima.co.uk: 'It was their Royal Highnesses The Duke and Duchess of Cambridge's preference.'

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Royal expert and correspondent Penny Junor also suggested that Charlotte's baptism in Sandringham and Louis' in London could also be down to convenience and logistics.

'When Charlotte was christened, the family was spending much more time in Norfolk, so Sandringham was the obvious choice for minimum disruption,' Junor explained.

'But now I think they are spending more time at Kensington Palace, so London makes more sense.'

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Last year, the royal couple announced that they would be relocating from the capital from Norfolk, where they were living due to William's role with the East Anglia Air Ambulance.

The Duke retired to become a 'full time royal', and their move also coincided with Prince George starting school at St Thomas's in South West London's Battersea.

Meanwhile, both church and chapel hold significance for Prince William and Kate Middleton – Princess Diana's coffin lay in the Royal Chapel before her funeral on September 6 in 1997.

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The Duchess also received her communion at the chapel before her royal wedding in 2011, while Princess Diana was christened at the Church of St Mary Magdalene back in August, 1961.

Earlier this week, the palace released a statement to announce Louis' christening: 'Their Royal Highnesses The Duke and Duchess of Cambridge are pleased to announce that the christening of Prince Louis will take place on Monday 9th July at The Chapel Royal, St James's Palace, London.'

It added that the third child of the royal couple will be christened by the Archbishop of Canterbury, the Most Reverend Justin Welby.

Prince Louis was born on 23 April at the Lindo Wing of St Mary's hospital in West London.